<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      .item {
        margin: 20px 10px;
        padding: 10px;
        border: 1px solid #6f6f6f;
      }
    </style>
  </head>
  <body>
    <div id="root"></div>

    <script
      src="https://unpkg.com/react@18/umd/react.development.js"
      crossorigin
    ></script>
    <script
      src="https://unpkg.com/react-dom@18/umd/react-dom.development.js"
      crossorigin
    ></script>
    <script src="https://unpkg.com/babel-standalone@6/babel.min.js"></script>

    <script type="text/babel">
      const root = ReactDOM.createRoot(document.querySelector('#root'))

      class App extends React.Component {
        constructor() {
          super()

          this.state = {
            students: [
              { id: 100, name: 'hxl', age: 18 },
              { id: 101, name: 'why', age: 18 },
              { id: 102, name: 'pink', age: 22 },
              { id: 103, name: 'lili', age: 16 }
            ]
          }
        }

        render() {
          const { students } = this.state

          // 选取>=18
          const filterStudents = students.filter((item) => item.age >= 18)
          // 选取前两个
          const sliceStudents = filterStudents.slice(0, 2)

          return (
            <div>
              {students
                .filter((item) => item.age >= 18)
                .slice(0, 2)
                .map((item) => {
                  return (
                    <div className="item" key={item.id}>
                      <h1>id: {item.id}</h1>
                      <h2>name: {item.name}</h2>
                      <h2>age: {item.age}</h2>
                    </div>
                  )
                })}
            </div>
          )
        }
      }

      root.render(<App />)
    </script>
  </body>
</html>
